[SCSI] ipr: fix possible false positive detection of stuck interrupt (a5442ba4) · Commits · 戴 / test

If the driver is getting flooded with interrupts, there's a possibility that the interrupt service routine could falsely detect a stuck interrupt condition and reset the adapter. This patch changes the logic such that the routine will loop back into the command processing code one more time after detecting the stuck interrupt signature. If there are no commands to process after that pass, and the interrupt is still not cleared, then the driver will print the "Error clearing HRRQ" message and reset the adapter. Signed-off-by:

Wayne Boyer <wayneb@linux.vnet.ibm.com> Acked-by:

Brian King <brking@linux.vnet.ibm.com> Signed-off-by:

James Bottomley <jbottomley@parallels.com>

drivers/scsi/ipr.c

+6 −6

Original line number	Diff line number	Diff line
		@@ -5149,21 +5149,21 @@ static irqreturn_t ipr_isr(int irq, void *devp)

		if (ipr_cmd != NULL) {
		/* Clear the PCI interrupt */
		num_hrrq = 0;
		do {
		writel(IPR_PCII_HRRQ_UPDATED, ioa_cfg->regs.clr_interrupt_reg32);
		int_reg = readl(ioa_cfg->regs.sense_interrupt_reg32);
		} while (int_reg & IPR_PCII_HRRQ_UPDATED &&
		num_hrrq++ < IPR_MAX_HRRQ_RETRIES);

		if (int_reg & IPR_PCII_HRRQ_UPDATED) {
		ipr_isr_eh(ioa_cfg, "Error clearing HRRQ");
		spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
		return IRQ_HANDLED;
		}

		} else if (rc == IRQ_NONE && irq_none == 0) {
		int_reg = readl(ioa_cfg->regs.sense_interrupt_reg32);
		irq_none++;
		} else if (num_hrrq == IPR_MAX_HRRQ_RETRIES &&
		int_reg & IPR_PCII_HRRQ_UPDATED) {
		ipr_isr_eh(ioa_cfg, "Error clearing HRRQ");
		spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
		return IRQ_HANDLED;
		} else
		break;
		}

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